Science: According to the top 500 list of the world’s most powerful supercomputers, compiled by a team of researchers in the US and Germany, China’s Tianhe-2 is now number one. Able to perform at more than 33 petaflops (a thousand trillion floating point operations per second), Tianhe-2 has surpassed the US’s Titan, which topped the previous list at some 17 petaflops. Not only does China have the fastest machine, but it is also second in the world in total number of supercomputers, although its total of 66 machines lags well behind the US’s 252. Despite the fact that Tianhe-2 relies on 3 million processor chips manufactured by Intel in the US, China is hard at work designing its own. With most of Tianhe-2’s other components designed and built in China, the country is becoming a strong contender in the race to build the first exascale computer, which would operate at speeds a thousand times greater than the current petaflops machines.